Centrifuge tests investigating the influence of pile cross-section on pile driving resistance of open-ended piles

Soil plugging in open-ended piles not only leads to an increase in compressive bearing capacity but also influences pile driving resistance. Numerous factors affect the tendency for soil plugging, for example pile geometry, penetration depth and installation method. In this study, the influence of the cross-sectional geometry of different open-ended piles (tubular, U- and sheet-piles) on the internal and external stress state at the pile toe is investigated. The underlying data were obtained from tests of pile installation (pile jacking) into dry silica sand conducted using a geotechnical beam centrifuge. During pile penetration the internal and external horizontal stresses at the pile toe were recorded to obtain the stress state inside the open-ended piles. The results are discussed with respect to the influence of the pile's geometrical properties (diameter of tubular piles, base width of U-piles and opening angle of sheet-piles) on the plugging tendency or the pile driving resistance. To conclude, a simple analytical approach based on equilibrium analyses is presented to predict the pile's bearing capacity.